The Cleveland Clinic announced today a Croatian-born cardiac surgeon will take over the helm of the locally based health-care system on Jan 1.

Tomislav Mihljevic will succeed Toby Cosgrove as the leader of the clinic. Cosgrove has been CEO for 13 years and has overseen the expansion of the system into several national and international locations including Ohio, Florida, Nevada, Canada, Abu Dhabi.

Dr. Mihaljevic, 53, will leave his post as CEO of Cleveland Clinic Abu Dhabi to take on this new role. He joined Cleveland Clinic in 2004 as a cardiothoracic surgeon specializing in minimally invasive and robotically assisted cardiac surgeries.

According to clinic officials, Cosgrove and Mihaljevic will work on a transition process together through the end of the year. Cosgrove will then assume an advisory role to be determined by the Board of Directors.

Cleveland Clinic is the largest employer in Northeast Ohio and one of the largest in the state. In 2016, the health-care provider reported earnings of $8.5 billion in revenues.